Metalworking



Oct. 27, 1936. c.- w. l- IAZELETT METALWORKING Filed Ma 5, 1953 8Sheets-Sheet 2 fi Q A iaNQQW.HAzE.LE-TT I N VN TOK W ATT QRNLJS Oct. 27,1936. w, HAZELETT 2,058,448

METALWORKIUNG Filed May 5, 1955 -v I 8 Sheets-Sheet 5CLAQENcEWI-IAmi-If'r 1N VEN TOR Arr'roRwige Oct. 27, 1936. c. w.HAZELETT METALWOTRKING Filed May 5, 1955. v 8 Sheets-Sheet 6 CLA ENcEWHAZELETT AT-roansge c. w. HAZELETT METALWORKING Filed May 5, 1933 8Sheets -Sheet 7 INVIEN R AT-roawzg Patented Oct. 27, 193.6

PATENT oFricE ,METALWQRG Clarence W. Hazelett, Rocky River, OhioApplication May 3, 1933, Serial No. 669,216

Claims (l. 22- 260.1)

My invention relates to metal working, and among the objects thereofarethe provision oi new and improved methods, the provision of new andimproved apparatus, and the provision of new and improved products.

In the drawings accompanying this specification and forming a part ofthis application, I

have shown, for purposes of illustration, certain. forms which myinvention mayassume.

In these drawings: Figure 1 illustrates diagrammatically certain phasesof my invention;

I Figure 2 illustrates the action in rolling a strip directly from themolten metal;

Figure 3 shows in elevation a mill particularly.

suited for the purposes of my invention;

Figure 4 is a vertical section taken generally on the, line 4-4 ofFigure -3, but showing the ladle partly in section;

Figure 5 is a detail sectional view of the ladle, taken on the line 55of Figure l;

Figure 6 is an enlarged fragmentary vertical sectional, view of therolls and the related parts,"

taken on the line 6-6 of Figure 3;

Figure 7 is a horizontal sectional view, taken on the line 'l 'l ofFigure 6;

Figure 8 is a vertical sectional view, taken on the line 8-8 of Figure6;

Figure 9 illustrates in detail the means for axially positioning theaxially adjustable roll, and for coating the-flanges;

Figure 10 illustrates the system for supplying the cooling water to therolls;

Figure 11 illustrates one method of controlling the operation of theapparatus;

Figure 12"shows an alternative form of roll construction;

Figure 13 illustrates a roll construction adapted to produce strip of L.cross section;

Figure 14 illustrates a roll construction. adapted produce strip of Ucross section;

Figure 15 illustrates a roll construction adapt..

ed to produce strip of I cross section;

Figure 16 illustrates a modification of the'cooling water system. toprovide variable cooling at diflerent points along the length of therolls;

Figure 17 illustrates an alternative method of determining the torquebeing required to operate the mill; r

Figure 18 illustrates a motor adapted to vary its speed automatically inresponse to the required torque; while- Figure 19 illustrates a controlsystem adapted to effect the same result.

In Figure 1 I have shown a horizontal mill 1i EISSED comprising a pairof horizontal rolls 2 and 3 mounted in juxtaposed parallel relation;these 'variable in speed, or alternatively, by inserting in the drive 8a variable speed device 9 of any suitable construction. 16'

Mounted at the ends of the roll 2 are a pair of flanges. I0 cooperatingwith the rolls 2 and 3 to define above the line i l of nearest-approachof the rolls 2 and 3 a space l2 for the reception of molten metal from areservoir l3, to form in the go space G2 a molten metal pool or lakel4."

The rolls 2 and 3 being below the temperature of fusion of the metal,the metal solidifies contiguous the rolls 2 and 3, and the solidifiedmetal is carried down to the bight II, and issues as the 2 That is, thestrip S may be passed from the mill I through a chamber l5 containingreducing gases intended primarily to prevent the formation of oxide onthe surfaces of the strip, and 35 then may be passed through are-rolling mill Hi, to vary the thickness of the strip, to bring thestrip accurately to'gauge, to change the characteristics of the strip,or to effect any other action that may be'desired. From the re-rolling Qmill IS the strip may pass through a. normalizing furnace IT, for heattreating the strip, and then through a pickling tank l8, containing acidor other solution suitable for removing any oxide present on thesurfaces of the, strip, and after 4 that, through a washing tank IQ, forwashing the strip 8 after the emergence thereof from the erations tosome extentv may be performed in 55 an order other than thatillustrated, and also, that any or all of these operations may beomitted, or other operations added, all as may be desired, but it is tobe noted that such of these operations as are included may be performedon the strip while the strip retains its original heat, and without anyre-heating, and further, that the passage of the strip immediatelythrough the reducing chamber [5, and then through the re-rolling mill l6before any further oxide has formed on the strip, is most effective tocompletely obliterate any trace of any surface cracks which may haveexisted in the strip as it issued from the mill i.

With apparatus of this type the characteristics of the strip S willdepend at least in large part on the extent of the solidificationcontiguous the rolls bight H. ficient solidified faces, and the metalwill pour through With the solidification entirely insufthe bight H as amolten stream. With some-- what greater extent of solidification therelatively thicker solidified faces will be of suilicient thickness toprevent the inner molten core fusing'through, and the molten core willsolidify between'the solidified surfaces, uniting the solidifiedsurfaces to itself, and thus to each other, and the strip S will issueas a cast strip.

I-find, however, that this characteristic continues only up to the pointwhere the extent of solidification exceeds the width of the bight II,and that beyond this point there occurs this marked difference, thatthereafter, by reason of the fact that the solidified metal delivered atthe bight H is of greater thickness than the bight II, the strip nolonger is a cast strip, but is distinctly a rolled strip, possessing thecharacteristics of the usual rolled strip, and other valuablecharacteristics in addition.

I find that the extent of solidification contiguou's the rolls 2 and 3,being dependent on the rate of solidification relative to the rate atwhich the strip is issued from the mill, is a result of various factors,including the nature of the metal itself, the temperature of the metalas delivered to the rolls, the length of the. arc of contact of themetal with the rolls, the temperature of the rolls, and the speed ofrotation of the rolls, and concurrently, that for any given metal I canmaintain thedesired. extent of solidification by maintaining constantthe relation between the various factors, and further, that I canmaintain this relation constant by controlling any one or more of thefactors, to compensate for variation in any one or more of the otherfactors.

For example, with any given metal I may maintain constant extent ofsolidification, despite variation in other factors, either bycoordinately varying the speed of rotation of the rolls, .or bycoordinately varying the rate of solidification, and I may coordinatelyvary the rate of solidification by coordinately varying the arc ofcontact of the metal with the rolls, or by coordinately varying thetemperature ,of the metal, or by coordinately varying the temperature ofthe rolls.

The speed of the rolls may be varied by va-' riation in the speed of themotor, 1, or by means of the variable speed device '9, and the arc ofcontact of the metal with the rolls may be varied by varying the depthof the molten metal lake It in the space I! between the rolls 2 and 3and the flanges l0, and the temperature of the 2 and 3 relative to thewidth of the the molten core will fuse through the metal may be variedby varying the temperature of the metal as supplied, or by preheatingthe metal as it is being supplied, or by heating the metal in the lakeH! in any suitable manner, such as by the passage of electric currenttherethrough either directly, or indirectly by inducing currentstherein. On the other hand, the temperature of the rolls may be variedby varying the cooling thereof, as, for example, by varying the settingof the valves 6, to vary the amount of cooling fluid supplied by theducts 4, or by varying the temperature of the cooling fluid, itself, asby inter-mixing steam and water in varying proportion.

Considering the factors mentioned, the extent of solidification isincreased by decrease in the speed of rotation of the rolls, or byincrease in the rate of solidificatiomand the rate of solidification isincreased by decrease in the temperathe metal be supplied at atemperature considerably in excess of its melting point, and that therolls be maintained at a temperature sufficiently low that the coolingfluid will not be so rapidly vaporized by contact with the rolls as toinsulate the rolls with a blanket of relatively poor conducting vapor,and under these circumstances it appears that the control of the extentof solidification can best be accomplished either by controlling thespeed of rotation of the mill or by controlling the arc of contact ofthe metal with the rolls.'

In connection with control of the operation of the mill, I find that forany given mill, and any given metal, and any given width of the bight,the torque required to drive the mill increases with increase in extentof solidification of the metal, so that an indication of the torquereextent to which the metal is being solidified, and

operation of the mill under substantially constant torque insuressolidification of the metal in substantially constant extent.

However, regardless of how the control may I be accomplished,coordination of the factors governing the extent of solidification is ofextreme importance, since variations will materially effect the qualityand characteristics of the product, even .if small in extent, and ofcourse, if larger, may result in appreciable damage and destruction,either by the passage of the metal through the rolls withoutsolidification, or in the other direction, by over-solidification to anextent suflicient to wreck the mill, whereas, by suitable coordinationit is possible to obtain and continuously maintain the desiredcondition, that is, solidification of the metal in a thickness somewhatgreater than the width of the bight II, whereby the metal is rolled bythe rolls 2 and 3, and the strip S issues as 8. rolled strip.

In Figure 2 I have illustrated the action which occurs in this respect,showing the rolls 2 and 3. the molten metal lake I4 in the space ll be--tween the rolls 2 and 3 and the flanges Ill (see Fig. 1), and thesolidification of the metal contiguous the rolls 2 and 8, into thestrips 23, increasing progressively in thickness until at their meetingpoint 24 they are of a combined thick- 76 ness materially greater thanthe width of the bight ii, and the further action of the rolls 2 and 3is distinctly and definitely a rolling action, to reduce the thicknessof the strips 23 to that defined by the width of the bight ll, so that,as

is to be expected from the fact that the stripis rolled, the strip Sissues in a thickness slightly greater than the width of the bight II,and further, by the extrusion action consequent to the rolling action,at a linear speed materially in excess of the peripheral speed of therolls 2 and 3;

From the foregoing it will be apparent that metal from a molten statemay be formed directly into a solid continuous strip, having thecharactertistic of a rolled strip, and certain other valuablecharacteristics in addition, and further, that this strip may be treatedandfabricated, even into a finished article, by a succession ofinstrumentalities operating continuously, while the metal still is hot.

In Figures 3 through 11 I have shown an embodiment of means for carryingout'this process.

Thisembodiment'comprises a horizontal mill '25 having a frame 26 inwhich is mounted ajirst pair of bearings 21 carrying a first roll shaft28 on which is mounted a-first roll 29.

Also mounted in the frame 26 is a second pair of bearings3il, carrying asecond roll shaft 3!, on which is mounted a second roll 32, and thissec- 0nd pair of bearings 39 is mounted in the frame 26 forreciprocation toward and from the first pair of bearings 21, toreciprocate the shaft 3| and roll 32 toward and from the shaft 28 androll 29, to vary the spacing between the rolls 29 and 32, and the widthat the bight 33. v

The reciprocation of each bearing 39 is controlled by a screw 34coacting with a nut 35 mounted in the frame 26; each screw 34'carries atits foot a swivel connection 36, connecting the screw with thecorresponding bearings 30, and at its head a pointer 31, cooperatingwith a dial 38 on the frame 26 to indicate at all times the position ofthe corresponding bearing 30.

Mounted between each bearing 27 and the contiguous bearing 30 is a coilspring 39, serving to hold the bearings and shafts and rolls inseparated position, prior to theintroduction of the metal between therolls.

The shaft 28 is driven from an electric motor 40 through suitablereducing gearing 4| connected to a pinion 42 meshing with a gear 43mounted on the shaft 28, and the shaft 3| is driven from the shaft 28 bymeans of inter-meshing gears 44 and 45 carried respectively by the shaft28 and the shaft 3| and provided with elongated teeth adapted to remainin mesh'for all.

permissible spacings of the rolls 29 and 32.

Mounted on-the roll 32 are a pair of flanges 46 secured in position bymeans of bolts 41 ex-.

tending through the flanges into the roll, and these flangesfli,together with the rolls 29 and 32, form the'spac'e 48, in which isretained the molten metal lake 49.

rial, without surface chilling or case hardening, and of a thicknessnot-less than twice the maximum thickness of strip intended to berolled, and then, to prevent contact between the male roll 29: and theflanges 46 acting to gouge splinters from the flanges 46, I prefer tomake the flanges 46 of a material definitely softer than the material ofthe roll 29. To secure uniform gage across the width of a strip I'findit desirable to concave one or both of the rolls 29 and 32, as shown inFigure 'l in connection with the roll 29.

I prefer to form each roll of homogeneous mate- In this particularembodiment of my invention the molten metal is supplied to the lake 49from'a heated ladle or furnace 50.

The particular furnace herein disclosed comprises a body 5| ofrefractory material, in the lower portion of which is a core 52 which isalso cf refractory material and is of a size to define between itselfand the body 5| a U-shaped passage 53 communicating'at both upper endswith the open interior 54 of the furnace 59. Extending through thecenter of the refractory core 52 is the center leg 55 of the core 56 ofa transformer, the primary winding of which, not shown, is connected toany suitable source of-alternating current, and the secondary of whichis constituted by the metal within the passage 53, so that the flow ofcurrent in the primary of the transformer induces a current in the metalwithin the passage 53, to heat this metal, and thus, by convection, toheat the entire metal within the furnace 59.

e The furnace is pivotally supported on the frame 26 of the mill 25 bymeans of a pair'of ears 51 carried by the furnace 50 and connected bypivot pins 58 to cooperating ears 59 carried by the upper plate 60 ofthe mill frame 26, and the furnace 59 delivers its metal through a spout5! which is positioned intermediate the ears 51 and pours into a trough62 from which the metal is delivered to the lake 49 through adistributor ram 64 having its cylinder 65 pivoted at 65 to lugs 61 onthe base 68 of the mill frame 26, and having its piston 69 pivotedat-lll to lugs H on the frame of the furnace 59.

The distributor 63, into which the molten metal is discharged by thetrough 52, is disposed in the space 48 between the rolls 29 and 32,intermediate the flanges 46, and with its bottom 12 lying below thenormal surface of .the molten metal lake 49, and discharges the metalinto the lake 49 through intermediate apertures I3 and end apertures 14,all disposed in the bottom 12, midway between the rolls 29 and 32.

The distributor 63 acts as 9. skim box to skim from the molten metal anydross which may come down the trough 52 and then, by introducing themetal into the lake 49 below the surface a of the lake, prevents theformation of any further dross, and in this way effectively prevents theintroduction of any dross into the lake 49,

mill. 7

The introduction of the metal into the lake 49 below the normal surfaceof the lake also serves to introduce the metal quietly, and with-'- outsurges, and this effect is augmented by the further fact that thedistributor 63, and the metal contained therein, operate as a baflle, todampvout the kinetic head-present in the metal as the metal comes downthe trough 82, so that the metal enters the lake 49 almost solely inresponse to gravity, and therefore, quietly, and with no particularforce or velocity, and in this The furnace is tilted by nfeans of ahydraulic 1 and therefore, into the strip produced by the v connection Ifind it desirable that the total head i the lake 49, but also, toprevent any flow or eddying of the metal within the lake 49, likely tocause any irregularity in the solidification of the metal contiguous therolls 29 and ,32, or in any way interfere with uniformity of thesolidification of the metal.

However, in order to assure further against the presence of dross in.the metal of the lake 49, I may envelope the surface of the lake 49 ina reducing atmosphere, as by means of ducts 15 disposed on the two sidesof the distributor 63, connected to a suitable source of reducingatmosphere, and provided with apertures by which the reducing atmosphereis discharged onto the surface of the lake 49, as indicated in Figure 6.Under many. circumstances I find it desirable that the metal shall bedelivered to the lake 49 ata temperature perhaps '75 degrees Fahrenheitin excess of the melting point of the metal, in order that any trappedgases may have ample opportunity to escape, before the metal solidifies;I may achieve this result by delivering the metal to the trough 62 at acorrespondingly high temperature. In thisconnection it may be noted thatI may preheat the trough 62, or the distributor 63, or both, as by meansof heaters 16 and/or. ll, positioned respectively above the trough 62and above the distributor 63, connected to a suitable source of gaseousfuel, and directing their flame respectively on the trough 62 and thedistributor 63.

In order to prevent penetration of the metal of the lake 49 between theroll 29 and the flanges 46 carried on the roll 32, I find it desirableto reduce thespaces between the roll 29 and the flanges 46 to a minimum,and to that end, to center the roll 29 accurately between the flanges46; as a matter of fact, this is particularly important when the metalis introduced at a temperature materially above its melting point, byreason of the rapid increase in the facility with which the metalpenetrates, as the temperature is raised.

To this end 1 mount the rolls 29 and 32 fixedly on the shafts 28 and 3|,support the shaft 28 against all axial movement, and then mount theshaft 3| for axial adjustment, as may be required to effect the desiredcentering of the roll 29 relative to the flanges 46.

Each of the rolls 29 and 32 is held against rotation on its shaft 28 or3] by means of a key I8 received'in cooperating keyways I9 and 89disposed respectively in the shaft 28 or 3| and the roll 29 or 32. Inassembling either roll upon its shaft the key 18 is placed in the shaftkeyway l9, and the roll, positioned with its keyway 89 inalinement-,with the key 18, is moved longitudinally along the shaftuntil an annular roll shoulder 8| abuts an annular shaft shoulder 82,whereupon the roll is held against further axial movement in thatdirection. At this stage the key i8 is fully engaged in the cooperatingkeyways 19 and 89, holding the roll firmly against any rotationrelativeto its "haft. Thereupon the segments of a segmental ring 83 areseated inan annular shaft recess 84, but projecting radially to overlie anannular roll shoulder 85, whereupon the roll is held against retrogrademovement longitudinally of the shaft, and therefore, against anyrelative movement axially of the shaft. I

A resilient split ring86 is then placed in position encircling thesegments of the segmental ring 83,

to lock these segments against any possible displacement. r,

The shaft 28 'is held against axial movement relative to the mill frame26 by means of collars 81 interposed between annular shoulders 88 on theshaft 28 and the bearing rings 89fixed in the mill frame 26. v

The means for effecting longitudinal adjustment of the shaft 3| in themill frame 26, and for holding the shaft 3| in its adjusted position,comprises thrust rings 90 held against rotation by pins 9| extendinginto the mill frame 26 and bearing against cooperating thrust rings 92flanking the flanges 46 which in turn flank the two sides of the roll32; the thrust rings 99 are moved along the axis of the shaft 3| toaxially position the shaft 3| and the roll 32, and are held in adjustedposition, by encircling rings 93 screwthreadedly engaging the thrustrings 96 and bearing against the sides of the mill frame 26.

In operation, the roll 29 being locked to the shaft 28,. and the shaft28 being fixed against longitudinal movement relative to the mill frame26, and the roll 32 beinglocked to the shaft 3|, the adjustment of theflanges 46 relative to the roll 29 is effected by rotation of theencircling rings 96, to project one of the thrust rings 99 and retractthe other thrust ring 96, until the shaft and roll and flange assembly3I-32-46 has been moved to the desired position, with the roll 29accurately centered between the flanges 46, and the shaft and roll andflange assembly 3 |-32-46 is held in this position, with the flanges 46accurately centeredadnXthe roll 29, by the irreversibility of theengagement of the encircling rings 93 with the thrust rings 90.

Further-to prevent entrance of metal between i at the edges of the stripan increased solidification of the metal relative to the extent ofsolidification of the metal centrally of the strip. This not only tendsto produce lack of uniformity in the strip, but further, tends to formadjacent the flanges 46 masses of. solidified material which willaccumulate to a considerable size before they pass between the rolls 29and 32, and then, in passing between the rolls 29 and 32, will exert apressure on the rolls which may crack 'a roll, break a bearing, or causeother injury to the mill, and to guard against this accumulation ofsolidified metal adjacent the flanges 46 I find it desirable to provideadditional traction at the ends of the rolls; I find that this may bedone by roughening the edges of the rolls 29 and 32, but roughening theedges of the rolls 29 and 32 produces a corresponding roughening of thesurface of th strip, which in many instances is objectionable, whereforeI prefer to provide this additional traction by having the inner ft :8of the flanges 46 relaprevent freezing of the metal to these inner facesof the flanges 46, and to this end I provide means for continuallyapplying such material to the inner faces of the flanges 46, as shownparticularly in Figure 9, wherein I have disclosed a holder 95 i inwhich is positioned a graphite block 96 spring pressed against theinner'face of the flange 46 by means of a coil spring 91. interposedbetween the base 98 of the block receiving recess 99 of the holder 9.5and the base I00 of the block 96.

However, I prefer also to provide means to compensate for the increasedcooling at the edges of the rolls, and I find that I may do thisconveniently by forming the end apertures 14 of the distributor 63 ofgreater size than the intermediate apertures 13, so that a greaterproportion of the molten metal is introduced into the lake 49 at theends of the lake, adjacent the flanges 46, and the lake is additionallyheated at the ends thereof, so that additional cooling is requiredadjacent the flanges 46.

Or I may accomplish this compensation by undercutting one or both of therolls 29 and 32, as indicated at IN on the roll 29, whereby-the strip isformed of increased thickness at its edges, and the increased coolingadjacent the flanges 46 is absorbed.

While either of these methods is satisfactory;

in actual practice I prefer to accomplish the compensation by thecoordinate use of both methods,

as herein illustrated,

Finally, just below the bight 33 I provide scrapers I 02, hearingagainst the rolls 29 and 32 and effective to separate the strip fromeither of the rolls to which it may tend to adhere.

To cool the rolls 29 and 321 provide two series of arcuate pipes I03extending beneath and to the rear of the rolls, apertured to spraycooling water against the surfaces of the rolls, and fed from headersI04 to which the cooling water is supplied by supply pipes I; to carryaway the cooling water I overlie these portions of the rolls 29'and 32with housings I01 in which the cooling water is collected, and fromwhich the cooling water is discharged through waste ducts I 08, and

I conveniently support these housings I01 by attaching their lower endsto cross bars I09 supported from the bearings 21 and 30.

The housing I01 for the roll 29 also cooperates with the distributor 63to removably support the.

trough 62.

Under certain circumstances there is a tendency for vapor from thecooling water to adhere to the surfaces of the rolls, and to form on thesurfaces of the rolls a sheathing blanket insulating the rolls from thesubsequent jets of cooling water, and therefore, reducing the coolingaction of the subsequent jets; to overcome this tendency I may providewipers wiping the rolls between successive rows of jets, such as thewipers H0 shown in Figure 6 as supported from the housings I01 and aswiping the rolls subsequent to the first two rows of jets.

To this same end I prefer to maintain the rolls under 400 degreesFahrenheit.

The supply of cooling water may be controlled manually by a manuallyoperated valve I II interposed in a main supply duct I06 from which thebranch supply ducts I05 are supplied, but I prefer to use this manuallyoperated valve I merely as a shut-ofi valve, to completely shut oif thesupply of cooling water when the. mill is not in operation, and duringoperation of the mill to control the supply of cooling water tothe-rolls 29 and 32 bycontrolvalves II2 interposed in the branch supplyducts I05 and actuated automatically in response to the temperature ofthe rolls 29 and 32.

Each valve H2 is provided in its web with a valve seat H3 in which seatsa valve head II4,

base quantity of cooling fluid to flow continuously, so that raising thevalve head II4 does not institute the flow of coolingwater, but merelyincreases the volume in which thecooling water is furnished.

It will be understood that under these circumstances'the base amount ofcooling water, permitted to flow by the by-pass aperture H5, is madesomewhat less than the amount required to cool the roll, and theadditional cooling water requisite for proper cooling of the roll isthen fugnished by intermittent opening of the valve I! To make thiscontrol automatic I provide for each valve I I2-a control comprising athermocouple IIB disposed in contact with the corresponding roll at apoint above the area where fore, responsive at all times to the lowesttemperature obtaining in the roll. Y

The conductors H1 and I I0 leading from the thermo-couple II6 areconnected to the two ends of the coil I I9 of a relay I20 arranged uponsuflicient energization of the coil H9, to close the relay switch I2Iand complete the circuit through a solenoid I 22 whose armature I23isconnected to the valve head I I4, to open the valve I I 2 whenever thesolenoid I22 is energized, and to hold the valve II2 open, so long asthe solenoid I22 coniglsies to be energized, or in other words, so ionthe current in the coil 1 I9 of the relay I20 is sufiicient to maintainthe relay switch I 2| in closed position, and therefore, since thecurrent in the coil H9 is the current of the thermal responsive to thetemperature of the thermocouple, so long as the minimum temperature ofthe roll exceeds a predetermined amount. Then when the temperature ofthe roll falls below this predetermined amount, the valve I I2 closes,to cut 01? the additional cooling water, and remains closed until thetemperature of the roll again exceeds the predetermined amount,whereupon the valve .I I2 again opens, to supply additional coolingwater, to reduce the temperature of the roll, and the cycle is repeated.

While I have shown this cooling water control only in connection withthe roll 32, it will be understood that it is employed'also inconnectionwith the roll 29, and further, that'the control employed inconnection with the roll 29 is in all respects a duplicate of thecontrol disclosed operate the mill, and therefore, to the torquerequired to roll the strip under the conditions of extent ofsolidification then existing, whereby'an ammeter I25 interposed in thecircuit of the motor I20, indicating directly the current re-' quired bythe motor I24, indicates also the torque required to drive the mill, andtherefore,

I the extent of solidification which is obtaining.

This arrangement contemplates also the actuation 011 the ladle tiltingram 64 under control of a three-way valve I26 connected to a duct I21leading to the cylinder 65 of the ram 64,

and arranged to connect this duct I21 either to a duct I28 leading to asuitable source of hytrol the arc of contact of the metal with therolls.

And with regard to these circumstances, the operator actuates thecontrol valve I26 in accordance with theindications of the ammeterfaster if the current required by the motor I24 decreases, to increasethe depth of the lake and the extent of solidification, and decreasingor discontinuing the I25, raising the ladle raising of the ladle 50 ifthe ammeter I25 indicates increase in current to the motor I24, thus tolower the height'of the lake 49, and to decrease the extent of thesolidification.

In this connection, I find that for metals such as zinc, brass, andsteel, it is desirable that the power used by the mill shall be not lessthan one horse power per foot of width of strip per foot per minuteperipheral speed of the mill.

Considering that'the ammeter I25 indicates immediately any change by themotor I24, and therefore, any change in the extent of thesolidification, it has been found that with this arrangement anexperienced operator may maintain the extent of solidification.

of the metal well, within the limits of the range over whichsatisfactory sheet is produced by the mill.

This arrangement, with its manual control of the tilting of the furnace50, also is particularly the furnace 50,

advantageous in connection with operation of the mill to produce acontinuous sheet requiring be contained in the furnace 50 at a singlecharge, so that the con-' of the mill requires refilling of tinuedoperation V and thereby, rapid movement 1 of the furnace 50 to retractit into position to an inner core I3I his receive a' further charge,andto return it to position to resume pouring of metal into the trough62, before the level of the lake 49 has decreased below the minimumlevel at which the mill continues to produce sheet of the desiredcharacteristic.

In Figure 12 I have shown an alternative roll construction comprisingrolls I30 each having surrounded by an outer shell I32 having aninternal diameter considerably in excess of the outside diameter of thecore I3I and supported by a supporting roller I33 mounted in anysuitable manner from the frame 26 of the mill 25. It willbe understoodthat the shell I32 and the core I3I are in engagement at the bight 33,and in order to'drive the shell I32 positively from the core I3I, thecore I3I and the shell I32 may be provided respectively with externalteeth I34 and internal teeth I35,

arranged to mesh at the point of engagement of the shell and the core,at the bight 33, or the teeth I34 and I35 may be omitted. 1

With'this construction the shell may be cooled both externally andinternally by coolingwater issuing from nozzles I36 and I3! locatedrespectively outside the shell I32 and in the space between the shellI32 and the core I3I, at a point directly opposite the pointofengagement of the core I3I and the shellv I32. The flow of cooling fluidto the nozzles I36 and I31 may be controlled manually by valves 'I30.located in the in the current required supply ducts 139, or may becontrolled automatically, as hereinabove described.

By means of this construction the rolls. I30 present substantially solidand unyielding surfaces to the metal at the bight 33, yet at the sametime are constructed to facilitate cooling of the shell, both by reasonof the ability to cool both internally and externally, and also, byreason of the fact that the shell, being solidly backed by the core atthe point of stress, may be relatively thin, to facilitate the coolingthereof.

This construction also has the further advantage, that the relativelyinexpensive outer shells may be replaced without replacement of theentire roll structure.

In Figures 13 through 15 I have shown alternative shapes of formingrolls, for rolling strip of various cross sections.

The roll I40 of Figure 13 is provided with a V-shaped recess MI, andwith flanges I42, and the cooperating roll I43 is provided with aV-shaped projection I44, cooperating with the V -shaped recess I4I ofthe roll I40 to define 'a V-shaped opening I45 at the bight of therolls, so that the rolls of Figure 13 will produce a strip of V-shapedcross section.

In Figure 14 the roll I46 is provided with a relatively flat contralportion I41, and at the edges thereof, just within the flanges I49, withrelatively deep recesses I48, and the cooperating roll I50 is formedwith a fiat face I5I of a width substantially equal to the entiredistance between the flanges I49, whereby there is defined at the bightof the rolls a U-shaped space I52, and the rolls of Figure 14 produce astrip of U-shaped cross section.

In Figure 15 the roll I53 is provided with a relatively flat centralsection I54, and with relatively deep recesses I55 on eachside thereof,just within the flanges I56, and the cooperating roll I51 also isprovided with a relatively fiat central portion I58 flanked byrelatively deep recesses I59, so that the rolls of Figure 15 define atthe bight an I-shaped space I60, and produce a strip of I-shaped crosssection.

. It will be understood of course that the strip may be formed of anyother desired cross sec- -tion, merely by proper configuration of thesurfaces of the rolls, and accordingly, that the sheet, V, U, and Icross sections herein shown, are merely illustrative of the crosssections which can be produced.

In Figure 16 I have shown means for cooling the rolls in varying degreeat various points along the length of the rolls, and Iflnd thisdesirable under certain circumstances, and with certain types of rolls,for example, in order to control the rolls against undue distortion,'oralternatively, to compensate for the additional cooling effect of theflanges by decreasing or omitting the cooling of the rolls adjacent theflanges. The particular means disclosed in Figure 16 comprises a coolingwater manifold I6I extending parallel to the roll I62, receiving fluidfrom a main duct I63 under control of a manual valve I64, oralternatively, 'under control of an'automatic control, as hereinabovedescribed, whichever may be desired, and then discharging the coolingfluid against the roll i62 through a plurality of branch ducts I65spaced along the-length of the manifold I6I and each controlled by anindividualbranch valve I66, whereby the relative amount of cooling waterin the various branch ducts I65 may be controlled and proportioned asmay be desired.

In controlling the operation of the mill manually I may substitute forthe ammeter indication of torque and extent of solidification a directtorque indication, and for this purpose may interpose a suitable torqueindicating device I61 in the drive 8 from the motor 1 to the rolls 2 and3, or, in the alternative, may employ the torque indicating mechanismdisclosed in Figure 17, wherein the mill motor I68 is mounted on a baseI69 pivoted at one end at I18 and resting at the other end I1I on aknife edge I12 carried on the short arm I13 of a lever I14 fulcrumed atI15 and having its long arm I16 connected by a link I11 to the short armI18 of a lever I19 fulcrumed at I88 and having its long arm I8I engaginga reciprocating bar I82 carrying a rack I83 which cooperatively engagesa pinion I84 mounted on a shaft I85 to which is secured an indicator armI86 moving over the scale I81'of an indicator dial I88. Depressionof'the free end I1I of the base I69 is opposed continually, inconstantly increasing amount as the free end I1I is depressed, by anybiasing means suitable for that purpose, such as a biasing meansutilized for that purpose in an ordinary scale.

n the other hand, while the coordination of the factors governing therelative extent of solidification of the metal, and the operation of themill, and the characteristics of the strip, may be controlled manually,and by control of the depth of the lake responsive to an indication ofthe torque required tooperate the mill, the coordination also may beefiected automatically, and in this connection, may beeffected-conveniently by controlling the speed at which the milloperates. I

For example, I may drive the mill by the differential series fieldcompound motor I89 disclosed in Figure 18 and comprising an armature I98acting under the influence of the field re sulting from the combinedaction of a shunt coil I9I and of a series coil I92 wound to set up afield opposite in direction to the field generated by. the shunt coilI9I, whereby, increase in cur-. rent through the motor I89, resultingfrom. increase in torque required toroperate the mill, caused byexcessive extent of solidification, by increase 'in the reverse seriesfield automatically will decrease the resultant field and increase thespeed of the motor I89 and of the mill, to decrease the extent ofsolidification, whereas decrease in torque required to drive'the mill,resulting from decrease in the extent of solidification, will decreasethe current through the motor I89, to decrease the field generated bythe series J coil I92, to increase the resultant field, and thus todecrease the speed of the motor I89 and of the mill, and thereby, toincrease the extent of solidification. The extent of the action of theseries field of course will be lirnited, as is well known in the art, toprevent preponderance of the series field under any'operatingconditions.

With a motor of this type, effecting control automatically, it isnecessary only to coordinate initially for the nature of the metal andthe width of the bight, afterwhich the motor I89,

properly constructed, will maintain the coordination automatically.

However, under many circumstances it is not 7 desirable tovary the speedof operation of the 1 mill, but on the contrary, is desirable tomaintain the mill at constantispeed, and to control some other factorgoverning the extent of solidification of the metal, and in thosecircum- 7 stances I may secure automatic control. by

' ing to a normally .motor starter I91 to the mill motor means of theFigure 19.-

In Figure 19 I have shown a main mill motor I93, which may be athree-phase squirrel-cage induction motor, connected by conductors I94and I95 and I98 to a mill motor starter I91 fed from line wires I98 andI99 and 288 and of any typesuitable for the purpose. The control meansof Figure 19 also comprises a control motor 28I of the three-phasewound-rotor induction type, connected by means of conductors 282 and 283and 284 to a reversing and control switch 285 which in turn is'connectedto the line wires I98 and I99 and 288 by means of connecting conductors286 and 281 and 288 and is operative in its upper position to connectthe control motor 28I for operation in one direction, and in its lowerposition to connect the control motor 28I for operation in the reversedirection, as will be understood from the diagram of connections.

Mounted on the shaft of the control motor 28I are three slip rings 289and 2I8 and 2, connected to the rotor winding as is well known in theart, and engaged by brushes, not shown, connected to conductors 2I2 and2I3 and 2I4 leading to resistances 2I5 and 2I6 and 2" connected togetherat their opposite ends by a T- conductor 2I8, whereby the control motor28I operates normally with the resistances 2| 5 and 2I6 and 2"interposed in the armature circuit. However, leading from the conductors2I2 and 2I3 and 2I4 connecting the slip rings 289 and 2I8 and 2I I tothe resistances 2I5 and 2I6 and 2" are conductors 2I9 and 228 and 22Ileadopen switch 222 adapted to connect together the conductors 2I9 and228 and 22I, to short circuit the resistances 2I5 and 2I6 and 2", toremove these resistances from the armature circuit of the motor 28I,thus to short circuit the armature of the motor 28I, to correspondinglyincrease the speed of the motor 28I, whenever the speed switch 222 isclosed. A

The control switch 285 is moved to forward position by means of aforward solenoid 223, and to reverse position by means of a solenoidreverse 224, and the speed switch 222 is moved.

to closed position by a solenoid 225, while the switch 285 includes alsoan auxiliary switch 226,

comprising a contact arm 221 adapted to engage with a forward contact228 when the control switch 285 is in forward position, and with areverse contact '229 when the control switch 285 is in reverse position.

interposed in the conductor I96 from the mill I 93 are a series ofrelays 238, 23I, 232, 233, 234, and 235, responsive to current flowingin the conductor I96, and set to operate at progressively increasingvalues, in the order named, the relays 238 and 23I and 233 being in thenature of overload relays, each opening on the passage of current inexcess of the value predetermined for 238 and 23I will be in closedposition, the relay 232 will be in open position, the relay 233 will bein closed position, and the relays 234 and ,235 will be in openposition, and this condition will continue until the current in the lineI96 control motor 20! reaches a value in excess of the predeterminedvalue at which the relay 230 will operate.

Accordingly, when the mill motor starter I91 is closed current will flownot only to the mill motor I93 but -also from the main conductor I96through conductors 236 and 231, the switch of the relay 230, conductors238 and 239, the coil 225 of the speed switch 222, and conductors 240and 24! and 242, back to the main conductor I95, thus energizing thecoil 225, to close the speed switch 222, to short circuit theresistances 2I5 and 2I6 and 2I1 in the armature circuit of the controlmotor 20!, to-connect the control motor 20! for operation at the maximumspeed. Simultaneously, the relay 23! also being closed, current willflow from the main conductor I96 through conductors 243 and 244, theforward coil 223 of the control switch 205, conductors 245 and 246, theswitch of the relay 23!, conductors 241 and 248, and conductor 242, backto the main conductor I95, to energize the forwardcoil 223 of thecontrol switch 205, to move the control switch 205 into the forwardposition, and to connect the to operate forwardly, and by reason of thefact that the speedswitch 222 is closed, to operate at maximum speed.Directly the control switch 205 has moved into the upper or forwardposition the switch arm 221 of the auxiliary switch 226 will engage theforward contact 228, and thiswill close a second circuit through theforward coil 223 of the control switch 205, extending from the mainconductor I96 through the conductors 243 and 244, the

- the control switch the relay 23!, but this will be ineffective, byreacreases further, the relay 2a! coil 223 of the control switch 205,the conductor 245, a conductor 249, the switch of the relay 233, aconductor 250, the auxiliary switch contact 228 and the auxiliary switcharm 221, a conductor 25!, and the conductor 242, ha k to the mainconductor I95.

As the current in the conductor I96 increases, the relay 230 will open,to open the circuit through the cell 225 of the speed switch 222, tointerpose the resistances 2I5and 2I6 and 2 I1 in the armature circuit ofthe control motor 20!, to reduce the speed of operation Then, as thecurrent in the conductor I96 inwill open, to interrupt the circuitthrough the forward coil 223 of 205 by way of the switch of son of thefact that the circuit through the coil 223 is also completed through theswitch of the relay 233. As the current in the main conductor I96increases still further, the relay 232 will operate to close its switch,but this also will be ineffective, because of the fact that by theconductor 252'the relay 232 is in series with the auxiliary switch 226of the control switch 205, and that the arm 221 of the auxiliary switch226 is in forward position, in engagement with the forward contact 228,rather than in reverse position, in-engagement with the reverse contact229, to which the switch .of the relay 232 is connected.

However, as the current in the main conductor I96 increases stillfurther, it reaches the value predetermined: for the relay 233, and therelay 233 opens, interrupting the last circuit through the forward coil223 of the controlswitch 205, to permit the control switch 205 to returnto neutral position, under the action of biasing means of any suitabletype, not shown. It will be noted,

however, that this still does not bring the switch arm 221 of theauxiliary switch 226 into contact with the reverse contact 229, so thatthe fact that .254, a conductor 251,

of the control motor 20!.

the switch of the relay 232 is closed still is of no consequence.

However, as the current in the main conductor I96 increases stillfurther, the relay 234 operates, to close its switch, and a circuit isthen completed from the main conductor I96 through the conductor 243, aconductor 253, the reverse coil 224 of the control switch 205,conductors 254 and 255, the switch of the relay 234, a conductor 255,and the conductors 24! and 248 and 242, back to the main conductor I95,to energize the reverse coil 224 of the control switch 205, to move thecontrol switch "205 into reverse position, control motor 20! foroperation in the reverse direction. When-the control switch 205 is thusmoved to reverse position the switch arm 221 of the auxiliary switch 226contacts the reverse contact 229, and this completes a second circuitthrough the reverse coil 224 of the control switch 205, extending fromthe main conductor I96 through the conductors 243 and 253, the reversecoil 224 of the control switch 205, the conductor the switch of therelay 232, the conductor 252, the contact 229, the auxiliary switch arm221, and the conductors 25! and 242, back to the main conductor I95.

If the current in the main conductor I96 continues to, increase, andreaches the value predetermined for the relay 235, the switch of therelay 235 will be closed, to completea circuit from the main conductorI96 through the conductor 236, a conductor 258, the switch of the relay235, a conductor 259, the conductor 239, the coil 225 of the speedswitch 222, and conductors 240 and 24! and 248 and 242,'back to the mainconductor I95, to again energize the coil 225 of the speed switch 222,to close the speed switch 222, to short circuit the resistances 2I5 and2I6 and 2" in the armature circuit'of the control motor 20!, to set thecontrol motor 20! operating again at full speed, but this time in thereverse direction.

However, if the current in the main conductor I96 decreases instead ofincreasing, it first will drop below thepredetermined value for therelay 234, and the relay 234 will open, to open the circuit through thereverse coil 224 of the control switch 205 by way of the s 'tch of therelay 234, but this will be immaterial, since an alternative circuit isclosed through the reverse coil 224 of the control switch 205, by way ofthe switch of the relay 232. As the current in the main conductor I96decreases further, the switch of the relay 233 will close, but this alsowill be immaterial, because the switch of the relay 233 is in ia-ryswitch226, and the switch arm 221 of the to connect the auxiliary switch226 is in engagement with the reverse contact 229 rather than with theforward contact 228.

' However, if the current decreases still further, the relay 232 willoperate, to open its switch, and this will break the second circuitthrough the reverse coil 224 of the control switch 205, and the controlswitch 205 will return to neutral position, to disconnect the controlmotor 20!.

Thereafter, increase in current in the main conductor I96 will repeatthe cycle heretofore de-' scribed, while further decrease in current inthe main conductor I96 will again close the switch of the relay 23!, toagain close the circuit through the forward coil 223 of the controlswitch 205, to operate the control motor 20! in the forward direction,until the current in the main conductor I96 exceeds the predeterminedvalue for operation of the relay 233, either with or without operationof the relay! to throw the control'motor I into full speed, according towhether or not the current in the main conductor I96 falls belowizslaievalue predetermined for operation of the relay Under thesecircumstances we have the situation that when the current to the millmotor I93 falls below the'value predetermined for the relay 23I thecontrol motor 2III operates in a forward direction until such time asthe current to the mill motor I93 exceeds the value predetermined forthe second succeeding relay 233. and then rests, until the current tothe mill motor I93 either again drops below the value predetermined forthe relay 2", in which case this cycle is repeated, or rises above thevalue predetermined for the relay 234, in which case the control motor2|II is operated in the reverse direction, until the value of thecurrent to the mill motor decreases to below the value predetermined forthe intermediate 7 relay 232, whereupon the control motor again rests,until the current to the mill motor I92 again rises above the valuepredetermined for the relay 234, in which case the control motor isagain actuated in the reverse direction, or alternatively, again fallsbelow the value predetermined for the relay 23 I in which case thecontrol motor 2M is again actuated in the forward direction. with thisaddition, that upon excessive departure from normal the relaysflfl and235 are brought into play, to short circuit the resistances in thearmature circuit of the control motor 2M, to increase the speed of thecontrol motor 2M, to expedite the return to normal.

I have heretofore pointed out that the torque required to drivethe millfollows the extent of solidification relativeto the spacing of therolls, and of course the current required by the mill motor I93 followsthe torque required to drive the mill, wherefore, the current in themain conductor I96, acting on the relays are and 23I and 232 and 233 and234 and 235, with any given metal, and with any given spacing of therolls, and with calibration accordingly, follows the extent ofsolidification of the metal, and the extent of solidification of themetal therefore maybe maintained constant automatically, merely bysuitably connecting the control motor 2M to any one or more meanscontrolling one or more of the factors governing the extent ofsolidification.

For example, I may'connect the control motor 2M through suitable gearingto the furnace 50, to control the pouring of the metal from the fur-,nace. 59 into the trough 62, or I may connect the control motor 2M tothe valves II2 controlling the supply of cooling water to the rolls, butwhatever arrangement is employed, the control means of Figure19,properly setto correspond to the nature of the metal being worked,and the width of the bight, will automatically coordinately vary any oneor more of the factors governing the extentof solidification,automaticallyto maintain constant the characteristics of the continuousstrip emerging from the mill.

. And of course, while I have described the apparatus herein illustratedwith particular reference to the combination where the extent ofsolidification is greater than the width of the bight of the rolls,so'that a rolled strip issecured, the apparatus herein shown may inlarge part be utilized as well for strip having other characteristics,such as that produced when the extent of solidification is not greaterthan the width of bight, and the strip is cast.

This is believed to hold true with respect to both time and temperature.In other words, the rate of the growth of crystalline microstructure isa function of both temperature and time.

The process disclosed causes mechanical distortionto operate on grainsize at times and temperatures approximating those of the instant ofsolidification much more closely than in any other process of which I amaware. Furthermore, when solidification completes the bridging of thespace between the two rolls, as at 24 in Figure 2, and every portion ofthe metal is instantaneously subjected to mechanical deformation, thebeginning of deformation not only is coincident with the firstoccurrence of ability to receive mechanical stress, but acts in thefirst instance on a body of material having a steep temperature gradientfrom the center to each outer surface. The hotter weaker central por-.

tions that will be at least accessible to mechanical deformation bylater rolling, either hot or cold, suffer the major part of themechanical deformation throughout the entire rolling action, andthereafter no temperature gradient approximating the initial gradientever can be obtained.

Whether the foregoing theory is correct or not, the fact is thatmaterial prepared as herein disclosed has ductility andhomogeneity'superior to the identical metal either hot rolled or coldrolled, and to such an extent as to permit a significant extension ofthe fields of use of such materials. For instance, brasses prepared inthis way can be subjected to drawing operations more severe-than werepreviously possible, and after drawing exhibit a much higher freedomfrom cracking, and a much superior surface finish.

In the preparation according to the invention of alloys capable ofhardening and tempering by heat treatment, it is possible to cool theouter surfaces below one or more of the transformation points of thematerial during thev initial formation of the strip. Obviously thisamounts to simultaneous solidification, temperature transformation, andmechanical deformation, thus accomplishing in a single momentaryoperation what heretofore has required at least two separate operations.I believe that it results also in outstanding improvements in themicro-structure, and in symmetry of the resulting product, effectingimprovement of the product of significance even greater than that of theelimination of the additional operation or operations.

From the foregoing it will be obvious that I have accomplished at leastthe principal objects of my invention, but at the same time it also willbe obvious that the disclosure herein is illustrative only, and that myinvention is not limited thereto.

Having now particularly described and ascertained the nature of my saidinvention, and in what manner the same is to be performed, I declarethat what I claim is:

1. The method of producing solid metal of substantially constant crosssection throughout its cause the ejection of solidified metal from thebight oi the rolls; and adding more heat to the zones adjacent to thedams than to the intermediate zones to control the thermal conditions sothat the temperature 01' the solidified metal at the bight oi the rollsis substantially the same in thezones adjacent to the dams and theinte'rmediate zones of the molten bath.

2. The method of producing solid metal or substantially constant crosssection throughout its length directly from a mass of molten metal whichcomprises establishing a bath of molten metal between a pair of adjacentand operatively associated rolls; providing a dam at each end of therolls to maintain the molten metal in said bath; maintaining said moltenmetal to a selected height in said bath; rotating said rolls to causethe ejection of solidified metal from the bight of the rolls; andcontrolling the thermal conditions so that the temperature of thesolidi- ,fied metal at the bight of the rolls is substan-,

tially the same in the zones adjacent to the dams and the intermediatezones by regulating the amount of heat supplied .to the various zones ofthe bath.

"3. The method of producing solid metal of substantially constant crosssection throughout its length directly from a mass of molten metal whichcomprisesvestablishing a bath of molten metal between a pair of adjacentand operatively associated rolls; providing a dam at each end of therolls to maintain the molten metal in said bath; maintaining said moltenmetal to a selected height in said bath; rotating said rolls to causethe ejection of solidified metal from the bight oi the rolls;andcontrolling the thermal condiv tions so that the temperature of thesolidified metal at the bight oi the rolls is substantially the same ,inthe zones adjacent to the dams and the intermediate zones of the moltenbath; the said controlling operation involving introducing a largeramount of molten metal to those regions of the bath adjacent to the'dams at the end of the rolls whereby compensation is made for excesscooling of said dams.

4. The method of producing solid metal of substantially constant crosssection throughout its length directly irom a mass of molten metal whichcomprises establishing a bath or molten metal between a pair of adjacentand operatively associated rolls; providing a dam at each end of therolls to maintain the molten metal in said bath; rotatingsaid rolls tocause the ejection of solidified metal from the bight of the rolls; andcontrolling the thermal conditionsso that the temperature oi thesolidified metal at the bight oi-the rolls is substantially the same inthe zones adjacent to the dams and the intermediate zones of the moltenbath; the said controlling operation involving the regulation of theheat supplied to the .ends of the rolls and associated dams wherebycompensation is eilected for excess cooling of the ends of the rollsand/or dams, and whereby the solidification of excessive solid metal atthe ends of the rolls is avoided.

5. The method of producing solid metal of substantially constant crosssection throughout its length directly from a mass oi. molten metalwhich establishing a bath of moltencomprises establishing a bath ofmolten metal between a pair of adjacent and operatively associatedrolls; providing a dam at each end of the rolls to maintain the moltenmetal in said bath; maintaining said molten metal to a selected heightin 'said bath; rotating said rolls to 'cause the ejection of solidifiedmetal from the bight oi the rolls; and providing the ends of the damswith a lower heat conductivity than the central zones of the rolls tocontrol the thermal conditions so that the temperature of the solidifiedmetal at the bight of the rolls is substantially the same in the zonesadjacent to the dams and the intermediate zones of the molten bath.

6. The method of producing solid metal of substantially constant crosssection throughout its length directly from a mass of molten metal whichcomprises establishing a bath of molten metal between a. pair ofadjacent and operatively associated rolls; providing a dam at each endof the rolls to maintain-the molten metal in said bath; maintaining saidmolten metal to a selected height in said bath; rotating said rolls tocause the ejection of solidified metal from the bight of the rolls; andproviding dams with lower heat conductivity than the rolls to controlthe thermal conditions so that the temperature of the solidified metalat the bight of the rolls is substantially the same in the zonesadjacent to the dams and the intermediate zones of the molten bath.

'7. The method of producing solid metal of substantially constant crosssection throughout its length directly from a mass of molten metal whichcomprises establishing a bath of molten metal- 'in said bath; rotatingsaid rolls to cause the ejection of solidified metal from the bight ofthe rolls; and expanding the cross section of the metal solidified atthe ends of the rolls gradually and outwardly. toform an expanded wedgeshape attached to and intended to form sides of the solidified metal tocontrol the thermal conditions so that the temperature of the solidifiedmetal at the bight of the rolls is substantially the same in the zonesadjacentto the dams and the intermediate zones of the molten bath.

8. The method of producing solid metal of substantially constant crosssection throughout its length directly from a mass of molten metal whichcomprises establishing a bath of molten metal between a pair of adjacentand operatively associated rolls; providing a dam at each end of therolls to maintain the molten. metal in said bath;

maintaining said molten metal to a selected height in said bath;rotating said rolls to cause the ejection of solidified metal from thebight of the rolls; and spraying less water at the ends of the rollsthan at the intermediate zones of the rolls to control the thermalconditions so that the temperature or the soiidifiedmetal at the bightoi the rolls is substantially the same in the zones adjacent to the damsand the intermediate zones of the molten bath.

9. The method of producing solid metal of subrolls to maintain themolten metal in said bath! maintaining said molten metal to a selectedbetween a pair of adjacent and operatively as- Y height in said bath:rotating said rolls to cause the ejection of solidified metal from thebight oi the rolls: and applying a heat insulating material to the damsto control the thermal conditions so that the temperature of thesolidified metalat the bight of the rolls is substantially the same inthe zones adjacent tothe dams and the intermediate zones of the moltenbath.

l0. The method of producing solid metal of substantially constant crosssection throughout its length directly from a mass of molten metal whichcomprises establishing a bath oi molten metal between a pair of adjacentand operatively associated rolls; rotating said rolls to cause theejection of solidified metal from the bight of the rolls; maintainingsaid molten metal to a selected height in said bath; and regulating thepower input applied to the rollsto not less than one horse power perfoot of width of metal per foot per minute oi peripheral speed ofadvance of the solidified metal to and through the bight of the rolls.

, 11. The method oi producing solid metal oi substantially constantcross section throughout its length directly from a mass oi molten metalwhich comprises establishing a bath of molten metal between a pair ofadjacent and operatively' associated rolls; rotating said rolls to causethe ejection of solidified metal from the bight of the rolls;maintaining said molten metal to a selected height 'in said bath; andregulating the temperature inthe molten bath in accordance with changesshown by a meter associated with the driving means for said rollswherebythe said temperature is increased with increases of said meter andisdecreased with decreases of said meter. j

12. The method of producing solid metal of substantially constant crosssection throughout I its length directly from a mass oi'molten metalwhich comprises establishing a bath of molten metal between a pair ofadjacent and operatively associated rolls; rotating said rolls to cause.the

ejection of solidified metal from the'bight of the rolls; maintainingsaidmolten metal to a selected height in said bath: and adding moltenmetal to said molten bath in amounts. depending upon indications oi ameter associated with the driving l means tor said rolls whereby thesaid amounts ftp are-increased with decreases in the'indications oi saidmeter and are decreased with increases in the indications of said meter.Y 7

13. The method of producing solid metal of substantially constant crosssection throughout its length directly from a mass of'molten' metalwhich comprises establishing a bath of molten metal between a pair ofadjacent and operatively associated rolls; rotating said rolls to causethe ejection of solidified metal from the bight of the rolls;maintaining said molten metal to a selected height in said bath; addingmolten metal to said bath; and varying said additions of molten metalwith changes indicated by a torque indicator o'peratively associatedwith the said rolls whereby the additions are increased with decreasesin the said indications of said indicator 1 lected height in said bath;rotating said rolls to cause the election of solidified metal from thebight of the rolls; and regulating the depth of the bath to a heightmore than the distance that the molten metal falls freely plus anystatic head of molten metal being fed to the bath whereby detrimentaleddies oi incoming molten metal are not created and solidified metaladjacent to the surface of the rolls and to the bight thereof is notdetrimentally aflected. l

15. The method of producing solid metal of substantially constant crosssection throughout its length directly from a mass of molten metal whichcomprises establishing a bath of molten metal between a pair oi adjacentand operatively associated rolls; providing a moving dam at each end ofthe rolls to maintain a bath of molten metal in said bath; maintainingsaid molten metal to a selected height in said -bath: rotating saidrolls to cause the ejection of solidified metal from the bight oi therolls; introducing'a stream. of molten metal into said bath; anddividing the said stream at a region closer to the surface of the baththan the depth thereof whereby detrimental eddies oi incoming moltenmetal are not created and solidified metal adjacent to the surface ofthe rolls and to the bight thereof is not detrimentally 'aiiected.

